Wireless communication networks are widely deployed to provide various communication services such as telephony, video, data, messaging, broadcasts, and so on. Such networks, which are usually multiple access networks, support communications for multiple users by sharing the available network resources. One example of such a network is the UMTS Terrestrial Radio Access Network (UTRAN). The UTRAN is the radio access network (RAN) defined as a part of the Universal Mobile Telecommunications System (UMTS), a third generation (3G) mobile phone technology supported by the 3rd Generation Partnership Project (3GPP).
Generally, wireless user equipment (e.g., referred to as mobile station (MS), mobile terminal (MT), access terminal (AT), etc. in various literature) configured for UMTS uses a Universal Integrated Circuit Card (UICC) (generally referred to as a SIM card) to store subscriber identity and for other security and authentication purposes. More recently, some UEs have multiple UICCs or SIM cards such that the user of the device can engage in calls or data communication on two or more different subscriptions. In general, each subscription is specified by a set of services and an identity associated with a network (e.g., UMTS). These subscriptions might be on the same network or different networks. A UE with multiple SIM cards is generally referred to as a multi-SIM device. Some such multi-SIM devices utilize a radio frequency (RF) resource (e.g., modem, transceiver), which is shared for accessing multiple subscriptions. However, there are certain limitations on carrying communications concurrently or simultaneously on multiple subscriptions while sharing the same RF resource.
As the demand for mobile broadband access continues to increase, research and development continue to advance multi-SIM wireless technologies not only to meet the growing demand for mobile broadband access, but to advance and enhance the user experience with mobile communications.